Safety elevator air-brake.



.- Safety brake operated by air mechanism which will.

:UNITED 'STATES PATENT osFroE.

FRED E. sMALL AND THEoDoRE M.. LATsoH, or Los ANGELES, cALr- FORMA.

' SAFETY ELEVATQR AIR-BRAKE'.

Specification of Letters Patent.

Patented' Dee. g5, 190e.`

.To 'aZZ whom it may concern:

Beit known that we, FREDE. SMALL and THEoDoRE M. LATsciI, citizens of the United States, residing at Los Angeles, in the county ofLos Angeles and State of California., have invented new and useful Improvements in following is a specification.

Our invention relates to means for prevent` ingv an elevator-cage from ascending or descending an elevator-shaft too rapidly; and the object thereof is to produce an elevator- ,automatically operate to prevent the elevator from moving up or down the shaft at a greater rate of s eed than is safe and which can also manual y be caused to operate. We

' scribe accomplish this object by the mechanism de# 'hereina'nd illustrated in the accompanying drawings, in which- Figurel is a bottom plan view of a portion "of -the elevator-'cage with a portion of our mechanism' in central section and a part broken away, the elevator guide-beams being .shown in cross-section. Fig. 2'is a longitudinal vertical section of the elevator cage and shaft, taken a little oil 'the center.

central rverticalsection of one of the valves used in our device.

. In the drawings, 5 represents the central vertical guide-rai s of the elevator-shaft 6. 7 is the elevator-cage, of any desired con- .I struction, whichis moved lin the elevatorshaft is a compressed-ain-storage tank `8,v

shaft by any desired mechanism.

Adjacent' to the bottom` ofthe elevatorwhichis su plied'with compressed airfrom anysuitable source.l From this storagetank leads a pipe 9,y which -11 is provided with check-valvell, which -prmitsthe air to entertthe auxiliary tank.4 i om thisauxiliary -storage-tank pipe13A leads to valve-chamber 14 of the air-controlling valve; (Shown in detail in Fig. 3.) A

pipe l 16' leads from valve-'chamber 14 and p a'sses'down throughA the elevator-cage'. At

Elevator Air-Brakes, of which the.

Fig: 3 is a' Y referably eX-'. tends a distance ofnearly onealf the'height of the elevator-shaft. To the upper end of.

- 49, shaft 50, and.'

a convenient point in the elevator-cage on 4sind-[pipe is a three-way valve 17, the handle 18 of which is normally held by spring 19 to iprovide an open way through the valve for the unobstructed passage of air throughthe which. shaft is' secured to the bottombf the cage.l Lever 27 is provided with a shoe 29 on its' free end', which when the brake is set, as shown .in Fig.. 1, engages the guide-'rail on one side thereof.` This ide-raily is refer-l ably a steel I-beam. Lin 26is pivotal y connected to one end of brake-lever 30, which is v pivotally mounted on'shaft-31, which shafty 1s secured to the bottom of thecage. .This lever is provided with a shoe 32, which engages the other side of theguide-rail when the brake is set. Piston 22 is rovided'with a stem 33,'which passes throug vguide 34, se

:cured tothe bottom of the car, and is' pr o-.

vided with a head 35, to which'is pivotally connectedlinks- 36 and 37 Link 36 is iv-A .on shaft4 42, which shaft is secured to the bot- -tomof'the ca e; Thefree end of this lever is providedwith shoe 43, which en 'ages'thel central guide-rail on the opposite s1 e to shoe` j -95 Aballgovernor 44 is secured'upon thetopy i 40 whenv the brakeis set.

of the cage, and may be operated convenient manner. In the drawings we 'have shown the same operatedl byr'means'rof the weight 45,"cord 46, pulleys 47 ,and48 pulley l evelears l'51"and -52.

The movable. collar .53 o thenfgelilor is Il operatively connected tol lever. 54;'which 4is'- pivotedl at 55 to a support 56,-s`eci1redfto the the cage move so rapidly either up or down `on cord 78 cou top of the cage. The other end of lever rests upon the outer end of bar 57, which is pivoted at 58 to a support 59, Jsecured to the to ofthe car. i Bar 57 rests upon stein 6() oi va ve 6l. Stem 60 passes through the hollow valve-stem 62 of valve 63, which has a central o ening therethrough which is normally he d closed by valve 61. Valve 61 is.

is held on its seat bywsfplrline; 73, coiled around4 stem 62 between stu g-box 74 and piston 67. A pipe 7 5 leads from the upper part of piston-chamber 68 and terminates Within the cage, and is provided with a petcock 76, by, means of which the air may be exhausted from the uper part of piston-chamber 68 when desir A port 77 in the side of the piston-chamber permits the air to pass freely in and out of the'same below piston 67. A cord 78 is attached to the outer end of bar 57- andl hangs down in the cage, so that, if desired, valve 61 can be manually operated. In the operationof our safety-brake should that it was not safe the ball-governor would operate lever 54 to depress the outer end of bar 5.7 This movement would depressvalve 61, which would open the upper end of piston-chamber 68 to air-pressure, which would act upon piston 67 to force valve 63 off itsA seat, thereby establishing communication vbetween the storage-tanks lled with cor1, pressed air and the piston-chambers and the pistons would through connecting mechanism cause the shoes on the ends of the brakelevers to engage the guide-rails and stop the motion of the car. Should the governor fail to Work, the olperator in the cage by pulling d operate ybar 57' to open valve 61 when the air would unseat valve 63,

Y asbefore explained. As soon as the brakeshoes stop t .ator would o :which would e motion of the cage the operppn the, petcock on pipe 75,

leed the upper part ot the chamber 68, and thereby permitvalves 6 1- and 63-to resume theirl normal positions.` He would then operate the `three-way valve to exhaust the air from the piston-chambers.

As soon as the air exhausts from the pistonl chambers springs 79 and 80, located on stems 23 and 3 3, respectively, between the heads ofsaid stems, and the guides therefor cause'the disengagement of theshoes Jrom we 'have provided an automatic safety air brake for an elevator-cage which will be powerful enough lo prevent the cage from falling when set and which. can be automatically or inanuallyset. Should the control mechanism by means of which the movement of cage is controlled by the operator get out of order, the operator could stop his cage at any desired floor, and if the supporting-cable for the elevator should break and the cage vstop between two loors the opel`- ator could by means of the three-way valve and cord 78 and cock 76 lower his car to any desired iioor below. f

By the use of the check-valve 11 should the hose break a suiiicient quantity oi' air Will be carried by the auxiliary tank to operate the brake-levers,

Springs 64 and 73 are preferably very light springs, intended to counterbalancc the Weight of the valves, and can be omitted.

Having described nur invention, what we claim is- .l

1. A safety elevator air-bral e, comprisiupr lbrake-levers ,pivotally connected to the cle-- vatorcage; an air-cylinder secured to the cage; pistons in said cylinder and attached tosaid levers; whereby when the pistons are moved in one direction the brake-levers are rendered operative to hold the cage against movementl and when moved in the opposite direction the brake-levers are disengaged and rendered inoperative; and means l'or supplying' said cylinders with air to operate said pistons.

2. A safety elevator air-brake, comprisingr brake-levers pivotally connected to the elcvator-cage; an air-cylinder secured to the rendered operative to hold the cage against movement and when moved in the opposite direction thebrakedevers are disengaged and rendered inoperative; means to supply air' to said cylinder to opera-te said pistons to renderthe cli1tclilevers inoperative; means to exhaust said air-supply from said air-cylinder; and means to return said levers to an in operative osition.

3. An e evator-shaft; guide-rails secured thereto; an elevator-cage' vertically move able in said shaft and guided by said rails; a

pair of brake-levers pivotally connected to thebottom of said cage, a pair on each side thereof; an' air-cylinder secured to the bot- -tom of said cage pistons in said cylinder and IIC pistons to cause said levers to engage said attached to said levers WherebT said levers Vhave hereunto snbscribed our names thisl ma be moved tflengfage the guide-railsor o 18th da'y of April, 1906. be isengaged t ere rom; means to supp y compressedfar to said cylinder to move said ATSCH guide-rails; and means `to cause the disen-l Witnesses: gagement offsaid levers from said guiderails; G. E. HARPHAM,` vIn Witness that we claim the foregoing we EDMUND A. 'STRAUSL 

